UK engineer sues BitMEX for 324.8 BTC over alleged unlicensed derivatives

A British software engineer is asking London’s Commercial Court to unwind years of BitMEX trades. Lewis Barber sued HDR Global Trading, the operator of the derivatives exchange, for the return of 324.8 BTC — valued at £20.4 million on 1 October in the claim, or about $27.2 million by Decrypt’s calculation — alleging the platform traded with him in the UK without Financial Conduct Authority authorisation.

What the claim argues

According to particulars of claim reviewed by Decrypt and reporting by The Guardian:

• Barber made about 2,294 trades from five accounts between 2018 and 2022; the suit focuses on the 1,053 that lost money.
• All were perpetual swaps — futures-like contracts with no expiry. The claim says each was a regulated activity BitMEX was not authorised to carry out in the UK, so the contracts are unenforceable under the Financial Services and Markets Act 2000.
• It alleges BitMEX did not block UK access, let new users pick the UK as residence, and ran global promotions, including a January 2019 ad in The Times. A March 2020 FCA warning that BitMEX may have offered regulated investments in the UK without authorisation is also cited.
• Barber also claims damages for deceit. His solicitors wrote to rescind the trades in December 2025.

Status of the case

The claim has been filed but not yet served. A BitMEX spokesperson told The Guardian: “No such claim has been served on HDR Global Trading Limited.” BitMEX itself shut down on 23 September after announcing the wind-down in July.

Seladore Legal, representing Barber, said other UK traders may have similar factual patterns and put potential aggregate exposure in the hundreds of millions of pounds — while stressing each case depends on individual trading history.

Wider context

BitMEX co-founders previously pleaded guilty to Bank Secrecy Act violations and were pardoned in March 2025; the exchange itself pleaded guilty in 2024 and was ordered to pay $100 million in January 2025. A proposed New York class action naming the co-founders remains separate from Barber’s UK claim.

This is a court filing, not a judgment. Outcomes remain uncertain until the claim is served and litigated.